President Barack Obama on Saturday night called for the repeal of the Defense of Marriage Act (DOMA) during his keynote address to the Human Rights Campaign’s 15th Annual National Dinner.

The law defines marriage as a legal union between one man and one woman, and prohibits legally married same sex couples from receiving federal benefits.

At the beginning of his speech, Obama joked that he talked "with your leader, Lady Gaga" and went on to tout his record on LGBT rights.

He noted that with his help the Matthew Shepard Act was passed, expanding the 1969 United States federal hate-crime law to include crimes motivated by a victim's actual or perceived gender, sexual orientation, gender identity, or disability.

Obama also noted that he had lifted the HIV travel ban and successfully fought to repeal the military policy "Don't Ask, Don't Tell."

"I need your help to fight for equality, to pass a repeal of DOMA, to pass an inclusive employment non-discrimination bill so that being gay is never again a fireable offense in America," the president told the audience of 3,000.

"And I don’t have to tell you, there are those who don't want to just stand in our way but want to turn the clock back; who want to return to the days when gay people couldn’t serve their country openly; who reject the progress that we’ve made; who, as we speak, are looking to enshrine discrimination into state laws and constitutions -- efforts that we’ve got to work hard to oppose, because that’s not what America should be about."

"We’re not about restricting rights and restricting opportunity. We’re about opening up rights and opening up opportunity and treating each other generously and with love and respect," Obama said.

The Respect for Marriage Act -- legislation that would repeal DOMA -- was introduced to the U.S Congress in March.

Watch video of Obama's speech, courtesy of HRC, below: